which pistons
 

as some of you know i blew my 5 speed up on the rolling road last week ive just bought a six speed and all the prop diff hubs etc but am thinking if its going to be in bits anyway why not change the pistons etc now i want to run 400ish got the turbo front mount intercooler injecters feul pump etc fitted already but have been told the pistons might fail as i have no idea what the tolerances of the parts are what do i need

Wiseco/Cosworth/Mahle/Manley...
Try realstreetperformance.com bud. What is it 2.0, 2.5 Open or closed deck?

its a 2.5 open deck im on the hunt for a cheap 2.5 engine so i can have it closed well they do a cnc cut friction fit inserts for them supposed to be a lot better than pinning them costs like 1700 though but they recon they will stand 650 bhp ok thats my target but for now i just want to run my standard engine at 400ish

anyone know owt about darton sleeves ?

i thought it was about 600 quid to have the block pinned? personally if i was going to run over 450 ish on a 2.5 then i'd look at getting it relinered as the 2.5 liners are thin and balloon at high power. but then at the cost of relinering or converting to cdb i'd go with a 2ltr cdb for reliability

yeah to get pinned but its 1700 to make it a cdb

or do you think darton dry sleeves and forged pistons and rods etc will do it

For that money you could easily go 2.1 or even 2.3 on closed deck blocks.
There have been a few 2.2T's kicking about in the for sale section recently.

The 2.5 is not an open deck, it's a semi closed deck. pinning the liners is more than enough for 400-450 although id also want forged rods at over 400hp. The liners should be fine at that power also. Going over 500hp will be expensive and not worth it in a road car imho.

if its just a road car then theres no need to convert to cdb or pin the liners. 450/450 in a classic is more than enough and very hard to beat as a road car imho. if your after more than 450 then i'd go 2 or 2.2 cdb

so will i need to pinn the liners to get 400/450 bhp or just change rods and pistons

something like eagle rods and weisco pistons do it or are the standard pistons ok

the standard 2.5 pistons are very poor, 380's about the upper limit on them but some people do get away with running 400. no need to pin the liners if your not going higher than 450. at 450 i'd say manley rods and wiseco pistons would see you right

Speak to A.p.i or Enginetuner for advice on the best route and parts to use as they are the most experienced when it comes to building engines. Listening to just members advice on here could cost you a fortune if it goes wrong.......

ill find them tomorrow and give them a call before spending my cash:)

Please PM Stu for details of AA status

but ive been told the power output and torque on a 2.5 closed deck will far exceed the 2.1 theres posts on here of ej25 reaching 800bhp with the right crank rods and pistons on a closed deck and the engine build cost is around 3200 i think thats quite cheap for the power not to say im going to do that because i actually use the car at weekends lol when its working anyway ive had it 9 weeks its spent 5 of them off the road already i want 420bhp safe and if it will cost less than 1500 im a happy man

Stadard block ok at sub 500 on a 2.5.

You'll need upgraded pistons (try Supertech) upgraded Rods (I have APi ones) and better head studs (I have Api 11mm ones)

Suggest you speak to David at APi for the low down.

EJ255 WRX block is open deck.........................

Running a 2.5 above 500 hp is:
A: unwise
B: expensive [ as in VERY ]
C: unreliable

For many reasons. Stay with 2.1 or 2.33 for that power level.

As if by magic, he appears! :D

My advice would be...
https://www.scoobynet.com/subaru-par...cdb-block.html

Someone needs to edit this page then :thumb:
http://en.wikipedia.org/wiki/Subaru_EJ_engine#EJ255